GB1152143A - Telescopic Boom for a Crane or the like - Google Patents

Abstract

1,152,143. Jib cranes. SARGENT ENG. CORP. 5 July, 1967 [17 Oct., 1966]. No. 31077/67. Heading B8B. A telescopic boom 16, Fig. 2, comprises four tubular sections: a base section 33, a fly section 34 and first and second inner sections 36, 37 respectively. From the retracted position shown in Fig. 3, the fly section 34 may be extended from the second inner section 37 by an hydraulic cylinder assembly 44 including a cylinder 46, pivoted at 48 to the rear end of the first inner section 36, and a piston-rod 47 pinned at 49 to a coupling member 51 slidable within the fly section 34. The coupling member 51 is connected to the fly section 34 by a pull-out pin 99 while the first and second inner sections 36, 37 are connected by an eye-pin 96. Extension of the piston-rod 47 thus extends the fly section 34. The pin 99 is then withdrawn and the piston-rod 47 retracted carrying the coupling member 51 from the dotted line position to the full line position in Fig. 9. The fly section 34, the second inner section 37 and the coupling member 51 are then connected by a pin 105 and the eye-pin 96 withdrawn. The second inner section, with the extended fly section 34, may then be extended by extension of the piston rod 47. A cylinder assembly 38 pivoted at 42 to the base section 33 and at 43 to the first inner section 36 is used to extend the first inner section 36, carrying the second inner section 37 and the fly section 34 with it. As shown, the boom 16 is included in a crane vehicle 15 with hydraulically operated outriggers 18 adjustable laterally of the vehicle frame 17. The boom 16 is luffed by a pair of hydraulic cylinder assemblies 23 and slued on a turn-table 21.